package com.atguigu.java1;

import org.junit.Test;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Consumer;
import java.util.function.Predicate;

/**
 * @author : leimingchao
 *
 * java内置的4大核心函数式接口
 *
 *      消费型接口：Consumer<T>       void accept(T t)
 *      供给型接口：Supplier<T>       T get()
 *      函数型接口：Function<T,R>     R apply(T t)
 *      断定型接口：Predicate<T>      boolean test(T t)
 *
 *
 * @date Date : 2021年06月19日 10:01
 */
public class LambdaTest3 {

    @Test
    public void test() {
        happyTime(500, new Consumer<Double>() {
            @Override
            public void accept(Double aDouble) {
                System.out.println("学习太累，去天上人间买了瓶矿泉水，价格为：" + aDouble);
            }
        });
        System.out.println("****************************");
        happyTime(400, money -> System.out.println("学习太累，去天上人间喝了口水，价格为：" + money));

    }

    public void happyTime(double money, Consumer<Double> consumer) {
        consumer.accept(money);
    }

    @Test
    public void test2() {
        List<String> list = Arrays.asList("北京","南京","天津","东京","西京","普京");
        List<String> filterStr = filterString(list, new Predicate<String>() {
            @Override
            public boolean test(String s) {
                return s.contains("京");
            }
        });
        System.out.println(filterStr);
        System.out.println("*******************************************************");
        List<String> filterStr2 = filterString(list, s -> s.contains("京"));
        System.out.println(filterStr2);

    }

    /**
     * 根据给定的规则，过滤集合中的字符串，此规则由Predicate的方法决定
     * @param list
     * @param predicate
     * @return
     */
    public List<String> filterString(List<String> list, Predicate<String> predicate) {
        List<String> filterList = new ArrayList<>();
        for (String s : list) {
            if (predicate.test(s)) {
                filterList.add(s);
            }
        }
        return filterList;
    }


}
